Endoscopes play a vital role for the visual examination and photographing of the cavities of internal organs of human body and the extraction of cellular tissues or other objects from the internal organs and, thus, various improvements have been made in endoscopes to enhance the performance efficiency, manoeuverability and durability of the endoscopes. As is well known in the art, an endoscope is a fiberscope using a flexible optical-fiber tube having various optical and biopsy elements attached to or incorporated in the leading end portion of the tube. During use of the endoscope, the optical-fiber tube of the endoscope is inserted into the cavity of the organ to be examined and is manipulated to move in various directions within the cavity of the organ from the manipulator unit to which the optical-fiber tube is fitted. The optical-fiber tube of an endoscope is, thus, subject to contamination with various foreign substances such as blood and other humors and, for this reason, must be washed and sterilized after each use of the endoscope. A washing apparatus tailored to endoscopes in general is therefore furnished and used where endoscopes are put to use in a hospital, clinic, infirmary or ambulance. Conventional washing apparatus for endoscopes are, however, becoming obsolescent for the endoscopes being improved at fast tempo.
A conventional endoscope washing apparatus uses a spray nozzle through which water or any disinfectant or sterilizing solution is to be sprayed onto the outer peripheral surface of the optical-fiber tube. The spray nozzle of the prior-art endoscope washing apparatus is arranged to discharge a stream of water or the disinfactant or sterilizing solution at a predetermined angle to the outer peripheral surface of the optical-fiber tube held in a predetermined position with respect to the optical-fiber tube. The spray nozzle thus arranged is moved along the optical-fiber tube from the vicinity of one end of the tube to the vicinity of the other end of the tube so that the optical-fiber tube contaminated is washed or sterilized throughout the length of the tube. One of the drawbacks inherent in an endoscope washing apparatus of this nature is that, if the optical-fiber tube of the endoscope to be treated by the washing apparatus has in its leading end portion an opening or corner which is angled with respect to the direction in which a stream of liquid is to be discharged from the spray nozzle, the stream of the liquid ejected from the nozzle is not permitted to reach such an opening or corner so that, if there is a mucous or solid substance deposited in the opening or corner, the substance can not be removed satisfactorily from the tube. Another problem encountered in a prior-art endoscope washing apparatus using a spray nozzle is that the washing apparatus is of no use for the cleaning of the passageways formed in the optical-fiber tube of an endoscope in which various conduits are incorporated in the optical-fiber tube for conducting water, air under pressure and suction therethrough and passing the wires connected to the forceps carried in the leading end portion of the tube. The present invention contemplates elimination of these drawbacks inherent in conventional endoscope washing apparatus.